RU2000435C1 - Method of draining off water from flooded workings - Google Patents

Abstract

Usage: in the coal industry. SUMMARY OF THE INVENTION: Two intersecting boreholes are drilled from the surface of the earth, one of which is vertically directed into a mine working associated with an existing drainage system, and the other inclined drill into a flooded mine. The intersection point of the wells is determined by the conditions of the drilling, taking into account the receipt of the permissible final head of the flooded production. An easily split pipe connection is used at the intersection of the wells, due to which it is possible to stop or reduce the flow of water at any time. The self-regulating system provides guaranteed safe conditions for the discharge of water for any period of time, eliminates spontaneous increase in flow or pressure.

Description

The invention relates to the mining, mainly coal, industry.

Two mutually intersecting vertical and deviated wells are drilled from the surface of the earth. A vertical well (vertical definition is conditional) is drilled to a mine (drift, lava, etc.) with which there is a connection with the existing drainage system.

An inclined well is drilled for a flooded mine, which must be drained, while a vertical one is crossed. The intersection point of the wells is determined based on the conditions of safe pressure, and also depending on what part of the flooded mine workout needs to be drained or maintained at a given pressure. Several inclined wells can be drilled.

A vertical well is cased with a column of pipes, the eatrub space is cemented.

An inclined well in the interval of weak rocks is equipped with a conductor; the annulus is cemented. After crossing a vertical well, but before entering the bottom into the zone of influence of the mine workings, but before entering the bottom into the zone of influence of the mine workings, the well is again cased, while the annular space is cemented only from the side to the intersection with the vertical well, where the column is equipped with an easily detachable connection.

During operation, the wellhead of this column is disconnected from the bottomhole to an easily detachable connection and the mouth is moved 2-3 m to the side. If necessary, the descent is stopped, the column is put into place. Further drilling of the deviated well is carried out according to conventional technology until the water level rises to the calculated mark. The inclined well is straightforward until it meets a vertical well, i.e. maximally reducingv

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curvature the well. It is known that by extending the core pipe and a number of other measures, the test crews reduce curvature to 0.05-0.10 m or less by the first 100 m of the deviated well, and when the well is vertical, the curvature is about 1.5 times less. You can define the condition of the meeting of two wells as the equation

Di + Og 2a.

where Di and D2 are the diameters of the wells;

a - possible curvature of an inclined well;

2a is the maximum possible total deviation of two wells from a given direction.

Thus, if we take 0.15 m as the maximum possible curvature of an inclined well, then taking into account the possible vertical curvature, the total curvature will not exceed 2a, i.e. 0.3 m. The sum of the diameters of both wells should exceed this value (300 mm).

For example, according to the required production rate of an inclined well, its internal diameter Da is calculated to be 100 mm. Then the inner diameter of the vertical well Di should be at least 200 mm.

The sequence of operations when performing the method is as follows:

1. A geological section of the rock strata is studied from the surface to the mine workings;

2. According to the materials of mining determine the pressure in the flooded mine workings;

3. Determine which part is flooded; mine workings need to be drained; To ensure the required level of safety, the drainage period is calculated, since the number of wells and their diameter are selected from the drainage period;

4. Using the given parameters, the intersection point of the vertical and deviated wells is determined;

5. Draw up a project for drilling wells and running water;

6. Drill a vertical well, casing a string of casing of the required diameter and cement the annulus;

7. Drill a deviated well, cross a cased vertical well at a predetermined depth, and fasten a casing string with an easily detachable connection at its point

intersection with vertical. Cement the annulus (from the bottom to the plug-in joint);

8 Lift the casing string from

detachable connection of an inclined well by 2-3 diameters thereof. The self-regulating drainage system will operate as soon as the casing of the deviated well rises

The positive effect of the application

The proposed method consists primarily in providing guaranteed safe conditions for a sufficiently long time, the possibility of stopping the discharge of water at any time or reducing flow rate. At the intersection of the wells, there is no large head of water, such a head will be in the bottom of a vertical well and will ensure that the well does not need to be cleaned systematically, as with conventional techniques. An increase in inflow to dangerous values is excluded, since the system is self-regulating. A positive point also in

There is the possibility of reducing inflow.

A particularly large effect will be obtained when using old, already unnecessary for the operation of ventilation wells and pits with a diameter of, for example, 800 mm and

more.

Claims (1)

SUMMARY OF THE INVENTION A method of draining water from flooded workings, including drilling wells, securing them with casing pipes, cementing the annulus and draining water, characterized in that, in order to ensure guaranteed safety by self-regulation of the process at design parameters, in the area of drainage a vertical well is drilled, and an inclined well is drilled into the flooded part of the mine workings with their intersection at the mark of safe head and water flow rate, the casing of the inclined well is equipped with an easy-to-connect connection at the point where it intersects with the vertical well, while the diameters of the wells are selected according to the water capacity , and the sum of the diameters of both wells is determined from the condition: Di + D2 2a, where a is the maximum possible curvature of the deviated well in the section from the mouth to the intersection with the vertical DI and D2 - diameters SOOHVRTSTO ZNNO vertical and inclined okvazhich